IN FLOWERING PLANTS, 149 
nation, its perforated apex projects beyond the aperture of 
the testa, and in some plants puts on the appearance of 
an obtuse, or even dilated stigma ; while in the ripe seed it 
is often either entirely obliterated, or exists only as a thin 
film, which might readily be mistaken for the epidermis of 
a third membrane then frequently observable." 
With regard to obliteration it is, I think, much to be doubt- 
ed whether it can take place to such a degree as to annihi- 
late the existence of pure vegetable membrane or of cellular 
membrane. For my own part I believe that a sufficiently 
careful examination will, in all cases, in which it does not ad- 
here to the outer coat, detect its presence. 
M. Brongniart says, that in all cases in which the nucleus 
is not absolutely naked, that there must necessarily be a 
membrane within the testa, derived from the nucleus, that as 
this always exists in the ovule, it ought always to exist in the 
seed, and that when it cannot be detected it is owing either 
to its excessive tenuity, or to its cohesion with the testa. 
We may infer hence, that M. Brongniart holds a similar 
opinion regarding all the other coats, that may exist in the 
ovulum. 
It would seem that Mr. Brown admits the possibility of 
obliteration, for in treating of the amnios, he says, “ in-such 
cases, however, its proper membrane is commonly oblitera- 
ted, and its place is supplied either by that of the nucleus, by 
the inner membrane of the ovulum, or, where both these are 
evanescent, by the testa itself." 
Generally speaking, the inner coat does not project beyond 
the outer foramen at the time of fecundation, occasionally 
however, it does, and even to a great length. M. Mirbel 
only knew of one instance of such protrusion in Statice. 
I must however observe, that this would according to Brong- 
niart be testa. See Memoire sur la Generation, p. 37, note. 
I may further state, that according to Mirbel, Brongniart 
has in his illustrations of Ricinus communis confounded the 
primine with the secundine coat, and that his nucleus is no- 
thing more than the secundine. To me, however, nothing 
can be clearer than the illustrations of Novice. 
